CH 7 Means of Egress
Dead-end corridor
Condition that exists when a corridor has no outlet to a means of egress and is more than 20 feet (6 m) in length.
means of egress components may be active, such as an automatic sprinkler system, or passive, such as doors, walls, and floors. Part of the inspector's job is to:
-Verify that doors, stairs, and walls conform to the adopted building and safety codes. • Recognize and evaluate those building components that serve as components of a means of egress. • Be aware of any exemptions in the means of egress requirements that are permitted in structures that are protected by automatic sprinkler systems. NFPA® 101, Life Safety Code®, contains specific examples of automatic sprinkler exemptions.
Two ways to make the stair enclosure smokeproof are
to pressurize it or to use natural or mechani- cal ventilation.
What is required to operate access-controlled egress?
-sensor on the egress side detects an occupant approaching. -Loss of power automatically unlocks the doors. — The doors must be arranged to unlock from a manual unlocking device that delays relocking for a mini- mum of 30 seconds and has a sign stating, "PUSH TO EXIT." — Activation of the building fire alarm, fire detection, or automatic sprinkler system will unlock the doors. — Some entrance doors in certain occupancy classes may not be allowed to be secured during periods of occupancies; or at all.
Markings are signs that direct occupants to the nearest exit and are no more than _______ ft from the nearest visible sign.
100ft.
How much force is required to release the latch on panic hardware?
15 pounds (7.5N)
How much force is required to set the door in motion on panic hardware?
30 pounds (15N)
In new buildings, model codes require that swinging or hinged doors serving as a component of a means of egress provide a minimum of ______________ of clear unobstructed width
32 inches (800 mm)
In multistoried buildings, the total occupant load of all floors served by the stairway is less than 50 people. In this case, stairways must be at least _________wide.
36 inches (900 mm)
In multistoried buildings, exit Stairways must be at least _____ wide unless the total occupant load of all floors served by the stairway is less than 50 people.
44 inches (1 100 mm). 50
Horizontal exits may be substituted for other exits if they do not compose more tha__ percent of the total exit capacity of the building.
50
The letters on an exit sign must be _____in height and the strokes of the letters are at least ____________wide
6 in heigh and 3/4 inches 19 (mm) wide.
Horizontal Exit
A path of egress travel from one building to an area in another building on approximately the same level, or a path of egress travel through or around a wall or partition to an area on approximately the same level in the same building
Fire escape ladders are only allowed for limited purposes if approved by the ____?
AHJ
Access-controlled egress.
Access-controlled egress. This type of hardware is designed to allow oc- cupants to egress freely while enabling the door to be secured from the outside (Figure 7.15). The occupant must use a security card or enter a code to gain entrance.
Clear Width
Actual unobstructed opening size of an exit.
Area of Refuge
An area where persons unable to use stairways can remain temporarily to await instructions or assistance during emergency evacuation.
In buildings that do not require panic hardware on exit doors, the model building codes define the types of door locks that may be installed: — exit doors can feature deadbolt locks that operate with the action of the latch and do not require keys, special tools, or knowledge to operate. — Thumb-turn bolts that operate independently of the door latch are examples of unacceptable locking devices on the egress (inside) side of exit doors (Figure 7.14). — Manually operated flush bolts or surface bolts are not permitted.
Bolt locks
The design of the area of refuge must meet the requirements of the
ICC/ANSI 117.1
NFPA 101, Life Safety Code, means of egress system may pass through the following:
Intervening room spaces • Doorways • Corridors • Passageways • Balconies • Ramps • Stairs • Courts • Yards • Horizontal exits
In multistoried buildings, exit stairs requirements for landings are:
Landings must be provided so that no flights of stairs are greater than 12 feet (3.5 m) high (Figure 7.20). •
Exit ramps info
New ramps must be at least 44 inches (1 100 mm) wide with a maximum slope of 1 to 12 (1 foot [300 mm] of rise for every 12 feet [3.5 m] of horizontal distance). The maximum length for a single ramp is 30 feet (9 m) without a landing.
Exit
Portion of a means of egress that is separated from all other spaces of the building structure by construction or equipment, and provides a protected way of travel to the exit discharge.
Exit Access
Portion of a means of egress that leads to the exit; for example, hallways, corridors, and aisles.
Smokeproof Enclosures
are stairways or stair enclosures (sometimes referred to as smoke towers) that are designed to limit the penetration of smoke, heat, and toxic gases into the stairway.
A means of egress system relies on a number of subsystems such as...
automatic sprinklers, or passive fire protection, such as fire-resistance-rated construction of doors and walls • Exit signs • Door hardware • Exit illumination • Handrails
Emergency lights are powered by ________ or an auxiliary power system
batteries
Horizontal exits
commonly used in (but not limited to) high-rise buildings and hospitals as a means of passing through a fire-barrier wall that separates two fire compartments in a structure
Exit doors may be required to open in the _________ of travel toward the primary exit, depending on occupancy and occupant load
direction
Exit passageways
exit passageway is similar to an exit stair enclosure, except that it is constructed in a horizontal plane. Exit passageways are designed to connect an interior exit stair or a hallway without stairs on the same level to an exit door on the structure's exterior. Exit passageways must be constructed of the same fire-resistant-rated material as the exit stairs.
A decorative ceiling may not be required to have any, _________but a ceiling that is part of a means of egress must have the same fire resistance rating as the walls.
fire-resistance rating
To provide a protected path of travel and qualify as an exit, ______________must separate interior stairs from other parts of the building
fire-resistant construction *least a 1-hour minimum fire- resistance rating when the exit connects three stories or fewer. Pg 258
The means of egress must terminate
in a public way or an area of refuge.
occupant load
is defined as the total number of persons for which the means of egress of a building or portion thereof is designed.
Panic hardware
may be required based upon occupancy classification and occupant load. Occupants should be able to operate panic hardware as follows: — Causing the latch to release by applying a force of no more than 15 pounds (7.5 N). — Setting the door in motion by applying a force of no more than 30 pounds (15 N) (Figure 7.13). In some occupancies, operating panic hardware to open exit doors activates an alarm. This alarm is intended to notify the employees or management or to help prevent theft.
FIRE WALLS: The fire-resistance rating is based on the type of the building has an automatic sprinkler system.
occupancy, building height, type of building construction, and whether
The occupant load for a building or room is established during the _______ process
plans review
exit discharge
portion of a means of egress that is between the exit and a public way
When the exit connects four or more stories, the separating construction must have a fire-resistance rating of at least ____?
two hours.
Delayed egress -
unlock upon operation of automatic sprinkler system, automatic fire detection system and unlock when power controlling the locking mechanism is lost.
Delayed egress doors require_____?
—Initiating the release mechanism by applying a force of no more than 15 lbs (67 N) must permit the door to open within 15 seconds, or in some cases, 30 seconds. — Opening the door will activate an audible signal. — Doors must be labeled with a sign stating, "PUSH UNTIL ALARM SOUNDS. DOOR CAN BE REOPENED IN 15/30 SECONDS." — Occupants must not have to pass through more than ONE door equipped with delayed egress before reaching an exit.
Gross
Refers to the entire square footage (m2) of a space measured wall to wall with no deductions for desks, files, movable partitions, or other items.
Net —
Refers to the gross square footage (m2) minus any space taken up by equipment, furniture, corridors, or other space that is not used for the oc- cupancy. For example, in an assembly occupancy such as a pool hall, only the clear floor space available for use is calculated — the gross area of the space minus the area taken up by the pool tables, counters, restroom spaces, office areas, and storage spaces.
Means of Egress
Safe, continuous path of travel from any point in a structure to a public way; the means of egress is composed of three parts: the exit access, the exit, and the exit discharge
A public way must also have a clear width and height of
10 feet (3 m)
Americans with Disabilities Act (ADA) of 1990 - Public Law 101- 336
Federal statute intended to remove barriers, physical and otherwise, that limit access by individuals with disabilities.
In multistoried buildings, exit stairs requirements for handrails are:
Handrails may be required for both sides of the stairs. -Stairs that are exceptionally wide may be required to have intermediate handrails in the middle of the stairs.
Common path of travel
Path that all occupants must travel in one direc- tion before reaching a point where they may choose between two separate and distinct paths leading to two separate exits (Figure 7.35). This distance is used in the calculation of total travel distance to an exit for the purpose of locating exits for a building or area.
means of egress system is composed of three basic elements
The exit access • The exit • The exit discharge
type of occupancy group also dictates the wall finish (paint, wallpaper, fabric, or other materials). Generally, NFPA® permits only the use of Class _______________ OR _________________interior finishes in exits or exit-access corridors.
A (0-25 flame-spread rating) or Class B (26-75 flame-spread rating)
Public Way
Parcel of land such as a street or sidewalk that is essentially open to the outside and is used by the public to move from one location to another.
Security bars hinder first responders by____?
Security bars slow access by fire and emergency services personnel and have been responsible for many fatalities.
In multistoried buildings, exit stairs requirements for stair treads are:
Stair treads must be solid and slip resistant. -Stair treads and risers must be in good condition to prevent tripping.
Horizontal exits
These exits require fire walls or fire-barrier walls with at least a 2-hour fire- resistance rating. A 11⁄2-hour fire-rated door assembly would be installed in the fire barrier to permit movement between the two compartments.
large loss-of-life fires, common factors continue to be cited even today:
• Locked or blocked exit doors • Improperly designed or marked exits • Inaccessible exits •Inadequate or nonexistent fire protection systems Combustible interior materials or contents Overcrowded occupancies
Two basic types of horizontal exits are:
•Ameansofegressfromonebuildingtoanareaofrefugeinanotherbuilding on approximately the same level. • A means of egress through a fire barrier or fire wall to an area of refuge at approximately the same level in the building that provides protection from smoke and fire.
Two of the most important life safety functions of doors are to:
•Separate occupants from the movement of fire, smoke, and other toxic gases • Serve as components of a means of egress system